Underfeed stoker.



W; J. KENNEY.

- UNDERFEED STOKER. APPLICATION FILED APR. 11, 1912.

' 1,196,869. I PatentedSept. 5,1916;

2 SHEETS-SHEET I.

UNITED STATES PANT OFFICE.

WILLIAM J'. KENNEY, 0F WILMETTE, ILLINOIS, ASSIGNOR TO UNDERFEED STOKERCOMPANY OF AMERICA, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

UNDERFEED STOKER.

Specification of Letters Iatent.

Patented Sept. 5, 1916.

Application filed April 11, 1912. Serial N0. 690,154.

To all whom it may concern:

Be it known that I, WILLIAM J. KENNEY,

a citizen of the United States, residing at Wilmette countyof Cook,State "of-Illinois,

have'in vented a certain new and useful Im- Kenney and Grohn Patent No.1,018,976 and has for its object to improve the same and increase itsefliciency. j The various features of novelty whereby my invention ischaracterized will hereinaf ter be pointed out with particularity in theclaims; but, for a full understanding of my invention and of its variousobjects and advantages, reference may be had to the following detaileddescription taken in connection with the accompanying drawings, wherein:

Figurel is a vertical section through a furnace arranged in accordancewith a preferred form of my invention; Fig. 2 is a horizontal sectionthrough the furnace above the retort and dead plates, thev dead plate onone side of the retort being removed to show the underlying mechanism;and Fig. 3 is a detail on a larger scale of one of the dogs and theadjacent portion of the dead plate which supports it.

Referring to the drawings,11 represents a furnace of any suitableconstruction in which is contained a. retort 2. At the sides and in rearof the retort-are stationary dead plates 3 and 4:, respectively, which,with the retort, divide the furnace into an upper combustion chamber anda lower air chamber. Fuel is supplied to the retort by means of asteam-operated ram 5 which forces fuel delivered from the lower end ofthe hopper 6' .into the front end of the retort. The ram is providedwith a pusher rod 7 which ex tends longitudinally through the retortnear the bottom thereof and serves to carry the a fuel toward the rear.In stokers of thiskind the fuel is caused to rise through the top of theretort where it is consumed and then swells out upon the dead plates atthe sides,

the lifting of the fuel being effected by the pressure of the ram andthe pusherv rod in the longitudinal direction. Various factors thereforeenter into the design. of the retort in order to produce an evendistribution of the fuel through the length of the retort, the mostsatisfactory expedient for securing this uniformdistribution being agradual decrease in the depth of the retort from the front end towardthe rear. Where the cllnkers and ashes are fed automatidally back'overthe dead plates it is desirable to have some drop from the front towardthe back of the furnace so as to permit gravity to assist in moving theclinkers and ashes. I have found after long experimentation that themost successful results are obtained by so proportioning and positioningthe retort that a total'angle of convergence of about six degrees fromthe front to the back is divided between an upward inclination of aboutthree degrees in the bottom of the retort and a downward inclination oflike amount in the top of the retort. rangement insures an evendistribution of the fuel'and at the same time permits the clinkers andashes to movefreely from the front toward the back under the influenceof the dogs to be hereinafter described.

In each of the side dead plates are one or more rows of oscillatory dogs8 having arms 9 which project down below the dead plates, and noses 10which are adapted to swing up and back from'positions in the plane ofthe dead plates, thereby breaking the clinkers and ashes from the sidesof the retort and feeding them toward the rear. The downwardlyprojecting arms of each row of dogs are connected together by alongitudinalbar which causes them to move in unison with each other.Extendin transversely beneath theretort is a roc shaft 12 having anupwardly projecting rocker arm 13 in the vicinity of each of the linksor bars 11. The

upper end of each rocker arm is secured to the rear end of one ofthelmks or bars by 100' This arin each particular installation.

in a suitable cylinder and having a connecting rod 17 secured to one endof an arm 18 extending radially from the rock shaft. 1 am also enabledto produce another result through the adjustment of the dogs. In stokersof this kind more or less of the air from the air chamber passes uparound the dogs through the openings in the dead plates in which thedogs lie; suchair aiding in the combustion of any unconsumed fuel whichreaches the dead plates. I so shape the openings and the dogs that thespace through which air. can pass up around the dogs in the normalposition of rest may be varied by the adjustment of the dogs in themanner heretofore described; thus controlling the flow of air throughthe dead plates and into the hot mass lying thereon. This feature willbest be understood from an examination of Fig. 3. The upper rear corner,40, of

each dog is in the form of a segment of a cylinder having its axiscoincident with the pivotal axis, 41, of the dog. The front edge orface, 42, of the dog is also a segment of a cylinder having its axis atthe'pivotal axis of the dog. The opening 43 in .which the dog lies hasits front and rear edges 44 and 45, respectively, curved eccentricallyto the pivotal axis of the dog; the arrangement being .such that as thetip 46 of the nose of the dog travels vertically through the dead plate,the distance therefrom to the front edge 44 of the opening varies, thisbeing also true with respect to the extreme rear end, 47, of the dog andthe rear edge, 45, of the opening. Consequently, by shifting the dogslightly when in its position of rest, the effective area of'the airpassages adjacent,

thereto and the amount of air passing up past theidog may be varied.

Assuming that Fig. 3' shows the position of restof one of the dogs: Thenby adjusting the turnbuckles to shorten the connecting rods slightly,all of the dogs are turned through a small angle in the clockwisedirection, decreasilng the size of the air passages; while uponadjusting the turn buckles so as to lengthen the connecting 'rodsslightly, the dogs are shifted in the counterclockwise direction and thearea of the air passages is increased.

It will of course be understood that the curvature of the dogs and ofthe edges of the openings in which they lie need not be just asillustrated and that my invention contemplates any arrangement forvarying the air passages adjacent to the dogs upon adjusting .the dogsin one direction or the other; Y

At the rear end of the dead plates is a discharge chute or passage 19into which the clinkers and ashes fall as they are'pushed over the rearedge of the dead plates. The top of thedischarge chute is normally covered by a perforated clinker breaker 20 which is preferably supportedupon a transverse oscillatory shaft 21 and has its upper surface in theform of an arc of a circle with its center at the axis of the shaft 21.Furthermore, the segmental clinker breaker is preferably connected atits front edge to the upper end of a transverse wing or plate extendinradially from the shaft 21 so as to form t erewith a powerful shearingmember cooperating with a transverse shearing member 23 along the rearedge of the dead plate to cut or break off .any considerable mass ofclinker which may overhang the discharge chute without falling into it.Normally the clinker breaker occupies the position shown in the drawingsand the clinkers and ashes, as. they are fed back, collectupon it; Byoscillating the shaft 21 in the clockwise direction, the clinker breakeris swung back out of the way and the overlying mass of clinkers andashes is scraped from it into the discharge chute by an overhangingportion of the bridge wall 24. The supporting shaft for the clinkerbreaker may be actuated in any suitable manner, conveniently by means ofa connecting rod 25 secured at its rear end to a crank arm 26 on theshaft and adapted'to be connected at its front end to the rocker arm 18.Thus when the main rock shaft 12 is oscillated to move 1 the oscillatingdogs, the clinker breaker is to give off some ofthe heat whichthey stillcontain; therefore. I have provided means for disconnecting theconnecting rod 25 from the rocker arm 18 at will. In the arrangementshown, the front end of the connecting rod 25 is made in the formof afork within I which the rocker arm 18 lies. In the underside of thefront ends of the prongs of the fork are notches .28 adapted to receivepins 29 projecting laterally from the rocker arm 18. i

30 is a lever suitably supported between its ends so as to have one endprojecting into proximity to the front end of the connecting rod 25, andon the connecting rod is a pin 31 which is adapted to be engaged by theadjacent end of the lever so as to permit the connecting rod to belifted clear of the pin on the rocker arm, as indicated in Fig.

1. When the parts are in this condition, the rocker arm may swing backand forth Without affecting the connecting rod 25. When the lever 30 isoscillated so as to lower the front end of the connecting rod, the pinson the rocker arm will drop into the notches on the connecting rod andthe connecting rod will be reciprocated by the rocker arm. The lever 30may conveniently be operated by means of a hand lever 32 projectingabove the floor in front of the furnace and connected to the lever 30'by a suitable link 33. By manipulating the lever 32, the man in chargeof the furnace may cause the ashesto be dumped whenever it is desirable,the clinker breaker remaining stationary at other times and permittingthe clinkers and ashes to accumulate thereon.

It may sometimes happen that there will be a little unconsumed or onlypartially consumed fuel among the clinkers and ashes when they reach theclinker breaker and pile up thereon, and I have therefore provided meanswhereby air may be caused to flow up through the clinker breaker andthrough the clinkers and ashes so as to complete the combustion of anycombustible matter remaining therein. This I accomplish by means of aconduit 50 leading from the air chamber beneath the retort into the ashchute at a point below the clinker breaker, together with a valve 51which may be controlled by a suitable handle 52 extending to the outsideof the furnace. The air chamber is supplied with air from a suitableblower, indicated conventionally, at 53, in the usual way so that astatic pressure is maintained therein. The bulk of this air passesupthrough the usual twyer blocks 54, some-of it through the spaces inthe dead plates around the dogs, and some of 1t, when the valve 51 iswholly or partially open, through the perforated clinker breaker. Thusthe fuel is positively supplied with air from the time-combustion beginsto the time the-waste clinkers andashes are dis-. charged, and thepossibility of fuel passing. through the furnace in an unconsumedcondition is reduced to a minimum:

While I have illustrated and described only a single preferred form ofmy inven--- retort for receiving clinkers and ashes therefrom, said deadplates being provided with openings therethrough, dogs mounted in saidopenings so as to be movable from a position of rest upwardly andrearwardly to break up the clinkers and ashes and carry them toward therear, operating mechanism for said dogs, means for adjusting saidmechanism to adjust the position of rest of said dogs, the dogs and theOpenings in which they lie being so constructed and arranged as to varythe clearance between the dogs and the edges of the openings upon avariation in the position of rest of the dogs,

and means for introducing air under pressure beneath the dead plates.

2. In combination, a furnace, a retort in the furnace, .dead plates atthe sides of the retort for receiving clinkers and ashes therefrom, saiddead plates cooperating with the retort to divide the furnace into anupper 3. In combination, a furnace, a retort in the furnace, dead platesat the sides of the retort for receiving clinkers and ashes therefrom,the retort and the dead plates dividing the furnace into an uppercombustion chamber andv a lower air chamber, twyer blocks on the retortfor admitting air from the air chamber, there being a discharge chuteforashes at one end of the retort, a perforated clinker breaker at theupper end of said ash chute, and means for.

introducing air under pressure into said air chamber and into theashchute at a point beneath said clinker breaker.

4. In combination, a furnace, a retort in'the furnace, dead plates atthe sides of the retort for receiving clinkers and ashes therefrom, theretort and the dead plates dividing the furnace into an upper combustionchamber and a lower air chamber,-

twyer blocks on the retort for admitting air from the air chamber, therebeing a discharge chute for ashes at one endof the retort, a perforatedclinker breaker at the upper end of said ash chute, means for delivering air under pressure to said air cham-' her, and a conduitleading from said air chamber into the ash chute at a point beneath saidclinker breaker.

[5. In combination, a furnace, a retort in the furnace. dead plates atthe sides of the retort for receiving clinkers andashes therefrom, theretort and the dead plates dividing the furnace into an upper combustionchamber and a. lower alr chamber,v twyer blocks on the retort foradmitting air from I chute for, ashes at one end of the retort, a'perforated clinker breaker at the upper end the air chamber, there beinga discharge FEB -9 of said ash chute, means for introducing air Intestimony whereof, I, sign this speciunder pressure into said anchamber, a con fication in the presence of two Witnesses.

condultQ duit leadin from the air chamber and opening into'th e ashchuteat a point beneath WILLIAM KENNEY' said clinker breaker, and a valve forcon- Witnesses:

trolling the passage of air through said JEANNETTE SHIVELY,

MARGARET FALAHEE.

